Need a professional mixpanel Jql expert

*** experienced freelancers only for a long-term relationship ***  hi, we use mixpanel for our product analytics, and i need a freelancer to which i can ask questions about the data and get answers :) a nice example is the flow example in mixpanel's jql documentation page: https://mixpanel.com/help/reference/jql/examples  In addition, because we can't export to csv People tables I also may want the freelancer to tell me the correct query for getting the list of People with certain traits (for example: all those that had a "Signed Up" event within the last 30 days, and that are from "United States"


Can you share specific experience with JQL queries in mixpanel?
What busieness cases did you handle?